The Maastricht Formation (Dutch: Formatie van Maastricht; abbreviation: MMa), named after the city of Maastricht in the Netherlands, is a geological formation in the Netherlands and Belgium whose strata date back to the Late Cretaceous, within 500,000 years of the Cretaceous–Paleogene boundary, now dated at . The formation is part of the Chalk Group and is between thick. It crops out in southern parts of Dutch and Belgian Limburg and adjacent areas in Germany. It can be found in the subsurface of northern Belgium and southeastern Netherlands, especially in the Campine Basin and Roer Valley Graben. Dinosaur remains are among the fossils that have been recovered from the formation.Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Cretaceous, Europe)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 588-593. .
Lithology The Maastricht Formation consists of soft, sandy shallow marine limestone (in Limburg locally called "mergel"), in fact chalk and calcareous arenite. These lithologies locally alternate with thin bands of marl or clay. The lower parts of the formation contain flint concretions. The upper parts can have shellrich layers. Its age is between about 70 and 66 million years, which puts it in the Maastrichtian, a stage that was named after the formation. The top of the formation has been identified as Danian (early Paleocene) in age. (2020), Type‐Maastrichtian gastropod faunas show rapid ecosystem recovery following the Cretaceous–Palaeogene boundary catastrophe. Palaeontology, 63: 349-367. doi:10.1111/pala.12462 (1996) The Cretaceous/Tertiary boundary in the Maastrichtian type area (SE Netherlands, NE Belgium); a historical account, Geologie en Mijnbouw 75: 107-118 The type locality is at the ruins of Lichtenberg castle on Mount Saint Peter, Maastricht.
Depositional environment Two primary environment-types have been described in the Maastricht Formation. The lower Kunrade Chalk representing a shallow, semi-lagoonal area near land of low relief which supplied terrigenous material. The Biofacies of the Kunrade Chalk are dominated by burrowing bivalves and abundant seagrass. In contrast, the upper Maastricht Chalk was deposited further offshore in clean carbonate sands. Periods of non deposition resulted in the lithification of sands forming hardgrounds that supported a diversity of echinoids and corals.
Stratigraphy The Maastricht Formation was first described by Belgian geologist André Dumont in 1849. The formation is subdivided in seven members, from top to bottom these are the Meerssen Member, Nekum Member, Emael Member, Schiepersberg Member, Gronsveld Member, Valkenburg Member and Kunrade Member. The members are often hard to distinguish.See for example: Stratigraphy of the ENCI quarry , by H. Zevenberg
The Maastricht Formation is overlain by the Paleocene Houthem Formation and was deposited on top of the older Gulpen Formation.
Vertebrate paleofauna
Dinosaurs
Dinosaurs reported from the Maastricht Formation Genus Species Location Stratigraphic position Material Notes ImagesAsteriornis A. maastrichtensis Limb bones and a mostly complete skull A stem-GalloanseraeBetasuchusB. bredai Geographically present in the Dutch province of Limburg."Femur.""Table 4.1," in Weishampel, et al. (2004). Page 78.An abelisauroid.Janavis J. finalidens An ichthyornithineMegalosaurusM. bredaiGeographically present in the Dutch province of Limburg.Reclassified as Betasuchus bredai.OrthomerusO. dolloiGeographically present in the Dutch and Belgian provinces of Limburg.A dubious hadrosaurid.Indeterminate euhadrosaurian remainsGeographically present in the Dutch province of Limburg.A hadrosauroid."Unnamed ornithurine"UnnamedAn ornithurine."Unnamed enantiornithine"UnnamedAn enantiornithine.
Mammals
Mammals reported from the Maastricht Formation Genus Species Location Stratigraphic position Material Notes ImagesMaastrichtidelphysM. meurismetiGeographically present in the Dutch province of Limburg."Right upper molar."A herpetotheriid.
Mosasaurs
Mosasaurs reported from the Maastricht Formation Genus Species Location Stratigraphic position Material Notes ImagesCarinodensC. belgicus C. fraasiJunior synonym of C. belgicus. GlobidensG. fraasiReclassified as Carinodens fraasi MosasaurusM. hoffmannii HolotypeM. lemonnieri PlioplatecarpusP. marshiPrognathodonP.? saturatorP.? sectorius
Testudines
Testudines reported from the Maastricht Formation Genus Species Location Stratigraphic position Material Notes ImagesAllopleuronA. hofmanniGlyptocheloneG. suyckerbuyki
Plesiosauria Indeterminate elasmosaurids
Bony fish Bony fish reported from the Maastricht Formation Genus Species Location Stratigraphic position Material Notes ImagesAlacongerA. triquetrusOtolithsA conger eel.AmpheristusA. sp.OtolithA cusk-eel.AnomoeodusA. foririTeeth, tooth platesA pycnodont.A. fraipontiA. subclavatusApateodusA. cornetiJaws, teeth, articulated skullAn ichthyotringid aulopiform.ArchaemacruroidesA. vanknippenbergiOtolithsA gadiform of uncertain affinities.ArgentinaA. voigtiOtolithsA herring smelt.ArgyroberyxA. dentatusOtolithsA beryciform of uncertain affinities.BelonostomusB. sp.Teeth, jawsAn aspidorhynchid.BeukidercetisB. grandisSkull bones, scutes, scalesA dercetid aulopiform.CaudadercetisC. taverniA dercetid aulopiform.CentroberyxC. fragilisOtolithA nannygai.CimolichthysC. sp.TeethA cimolichthyid aulopiform.CretaserranusC. maastrichtiensisOtolithsA perciform, possibly a serranid.CyranichthysC. jagtiArticulated specimen, scutesA dercetid aulopiform.C. sideralisDercetisD. triqueterArticulated specimensA dercetid aulopiform.EnchodusE. faujasiJaws with teethAn enchodontid aulopiform.HoplopteryxH. sp.Articulated specimensA trachichthyiform.?Ichthyotringa?I. taverneiOtolithsAn ichthyotringid aulopiform.OphidercetisO. italiensisSkull bones, scutesA dercetid aulopiform.ParaulopusP. sp.OtolithA cucumberfish.PetrodercetisP. bidirectusA dercetid aulopiform.PfeilichthysP. pfeiliOtolithA holocentriform of uncertain affinities.PlesiopomaP. otiosaOtolithsA percomorph, possibly a lanternbelly.RhinocephalusR. cretaceusOtolithsA hake.SaurocephalusS. woodwardiiTeeth, jaws, vertebraeAn ichthyodectiform.SevernichthysS. sp.OtolithA beardfish.SillaginocentrusS. alienusOtolithA holocentriform of uncertain affinities.?Sparidae indet.OtolithsA potential seabream, but may be another non-percomorph teleost instead.Tetraodontiformes indet.Scale platesA tetraodontiform.
Invertebrate paleofauna Invertebrates reported from the Maastricht Formation Genus Species Location Stratigraphic position Material Notes ImagesMaastrichtiocarisM. rostratusMiddle Meerssen MemberCarapaceA cyclidan crustcean, youngest member of the group, has also alternatively been suggested to be a crab.
Plants
Taxa Species Locality Material Notes ImagesAraucaria?A?. sp.Seed-cone scalesIdentified as Araucaria, in contradiction to reports citing no Araucarian pollen present.BrachyphyllumB. patensLikely belongs to Cheirolepidiaceae.sp. 1Belongs to Cheirolepidiaceae.sp. 2Possibly conspecific with sp. 1.CryptomeriopsisC. eluvialisBelongs to Taxodiaceae.CunninghamitesC. ubaghsiiLikely belongs to Taxodiaceae.ElatidopsisE. cryptomerioidesBelongs to Taxodiaceae.MosacaulisM. spiniferStems and associated foliage, Seagrass convergent.PityophyllumP. sp.Pinaceous needles.Thalassocharis T. bosquetiiSeagrass stems and roots.Thalassotaenia T. debeyiSeagrass leaves, similar to Posidonia.
See also
List of dinosaur-bearing rock formations
References